Study to Evaluate the Effect of Multiple Doses of Rifampicin on the Multiple-dose Pharmacokinetics of Linagliptin in Healthy Volunteers

Inclusion Criteria: * Healthy males and females according to the following criteria: Based upon a complete medical history, including the physical examination, vital signs (Blood Pressure (BP), Pulse Rate (PR)), 12-lead Electrocardiogram (ECG), clinical laboratory tests * Age 18 to 50 years (incl.) * BMI 18.5 to 29.9 kg/m2 (incl.) * Signed and dated written informed consent prior to admission to the study in accordance with Good clinical practice (GCP) and the local legislation Exclusion Criteria: * Any finding of the medical examination (including BP, PR and ECG) deviating from normal and of clinical relevance * Any evidence of a clinically relevant concomitant disease * Gastrointestinal, hepatic (incl. porphyrias), renal, respiratory, cardiovascular, metabolic, immunological or hormonal disorders * Surgery of the gastrointestinal tract (except appendectomy) * Diseases of the central nervous system (such as epilepsy) or psychiatric disorders or neurological disorders * History of relevant orthostatic hypotension, fainting spells or blackouts. * Chronic or relevant acute infections * History of relevant allergy or hypersensitivity (including allergy to drug or its excipients) * Intake of drugs with a long half-life (more than 24 hours) within at least one month or less than 10 half-lives of the respective drug prior to administration or during the trial * Participation in another trial with an investigational drug within two months prior to administration or during the trial * Smoker (more than 10 cigarettes or more than 3 cigars or more than 3 pipes/day) * Inability to refrain from smoking on trial days * Alcohol abuse (more than 30 g/day if male, more than 20 g/day if female) * Drug abuse * Blood donation (more than 100 mL within four weeks prior to administration or during the trial) * Excessive physical activities (within one week prior to administration or during the trial) * Any laboratory value outside the reference range that is of clinical relevance * Inability to comply with dietary regimen of trial site * Thrombocytopenia or increased liver function tests (i.e. Alanine transaminase (ALT), Aspartate transaminase (AST), bilirubin, Alkaline phosphatase (AP), Gamma-glutamyl transferase (GGT)) at screening * prior rifampicin exposure For female subjects: * Positive pregnancy test, pregnancy or planning to become pregnant during the study or within 2 months after study completion * No adequate contraception during the study and until 1 month after study completion, i.e. not any of the following: IUD (intrauterine device), sexual abstinence for at least 1 month prior to enrolment, vasectomised partner (vasectomy performed at least 1 year prior to enrolment), or surgical sterilisation (including hysterectomy). Females, who do not have a vasectomised partner, are not sexually abstinent or surgically sterile have to use an additional barrier method (e.g. condom, diaphragm with spermicide) * Lactation